Home Air Filtration for Traffic-Related Air Pollution

NCT04279249 | Completed

• 2 other identifiers: 20-109-21R01ES030289
• Study Type: interventional
• Target: 156
• Locations: 1 country
• Sites: 1

Brief Summary

This study is a blinded randomized crossover efficacy trial (N=172 households consisting of 207 participants) of High Efficiency Particulate Air (HEPA) filtration in near-highway homes that lack mechanical air-handling systems. Households will be randomized to 30 days of either filtration or sham filtration followed by a 30 washout period with a subsequent 30-day period of the alternative assignment. Room air filters that are commercially available will be placed in the bedroom and living room of each home. The investigators will measure UFP and PM2.5 concentrations in 20% of the homes during filtration and sham periods and assess personal exposure in a subset of participants. The investigators will also assess chemical composition of particulate air pollution in 10 homes/year for exploratory purposes that could lead to future lines of research. The primary health endpoints will be participants' hsCRP and peripheral blood pressure, measures that the investigators have used in multiple observational studies of UFP as well as in pilot filtration intervention studies. Secondary biological measures that contribute to understanding biological pathways will be IL-6 (inflammation), D-dimer (coagulation), metabolome, central pressure and arterial stiffness. The primary intention to treat analysis will compare outcomes between HEPA filtration to sham filtration. The investigators will have 80% power to detect a difference of 0.6 mg/L in change in hsCRP and a difference in reduction in systolic blood pressure of 3.5 mmHg compared to participants who receive no filtration. Having participants serve as their own controls in the within-subject comparisons of intervention effectiveness increases statistical power and eliminates the possibility of baseline imbalances in demographic and clinical characteristics. A social science evaluation will inform final adjustments to the investigators' approach at the start and also assess participant acceptance and experience with the intervention at the end. The investigators' primary innovation is that this will be the first near highway HEPA intervention trial that is large enough and careful enough to be policy-relevant.

Conditions

Cardiovascular Risk Factor; Blood Pressure

Keywords

Ultrafine Particles (UFP); HEPA; Traffic-Related Air Pollution; Air Filtration; In-home

Outcome Measures

Primary Outcomes (2)

• Change in Systolic Blood Pressure at 1 Month

  Seated blood pressure measured using ambulatory monitors

  measured at study onset and 30 days

• Change in High Sensitivity C-Reactive Protein (hsCRP) at 1 Month

  inflammation marker assayed from blood samples

  blood sample taken at study onset and 30 days

Secondary Outcomes (1)

• Change in D-dimer at 1 Month

  blood sample taken at study onset and 30 days

Study Arms (2)

HEPA Filtration

ACTIVE COMPARATOR

Other: HEPA Air Filtration

Sham HEPA Filtration

SHAM COMPARATOR

Other: Sham HEPA Air Filtration

Interventions

HEPA Air Filtration OTHER

2 HEPA air filters placed in home (one in bedroom, one in living room) for 30 days

HEPA Filtration

Sham HEPA Air Filtration OTHER

2 HEPA air filter devices with filter removed placed in home (one in bedroom, one in living room) for 30 days

Sham HEPA Filtration

Eligibility Criteria

• Age: 30 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• residence within 200 m of interstate I-93 in Somerville
• live at home full time
• cognitive ability to answer questionnaires
• able to speak English/Spanish

You may not qualify if:

• in-home mechanical air handling system with forced air pushed through vents
• smoker or lives with smoker(s)
• history of heart attack, stroke, or other major cardiovascular outcome
• taking anti-hypertensive or anti-inflammation medications
• occupational or other routine high exposures (away from home) to traffic pollution
• extensive use of candles/incense inside the home
• Preferred Criteria:
• residents of apartments with highway-facing windows and that are no more than 3 stories tall

Sponsors & Collaborators

• UConn Health: lead
• Somerville Transportation Equity Partnership, Inc.: collaborator
• Tufts University: collaborator
• Olin College of Engineering: collaborator
• Welcome Project Inc: collaborator
• National Institute of Environmental Health Sciences (NIEHS): collaborator

Study Sites (1)

UConn Health

Farmington, Connecticut, 06032, United States

Location

Related Publications (1)

• Singh-Smith K, Sprague Martinez L, Eliasziw M, Lerman Ginzburg S, Hudda N, Betz GM, Gurcan A, Vazquez-Dodero T, Mertl A, Goldstein-Gelb W, Zamore W, Brugge D. Reaction to at-home air purifiers installed to reduce traffic-related air pollution in near-highway residences. Trials. 2024 Aug 19;25(1):551. doi: 10.1186/s13063-024-08388-z.

  PMID: 39160612 DERIVED

Study Officials

• Doug Brugge, PhD

  Tufts University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: PREVENTION
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Model Details: This study is a randomized crossover trial, in which study participants are randomly assigned (by computer) to different arms of the study in which they receive different interventions - in this case, either the HEPA air filter or the sham filter. The two arms will run concurrently, rather than sequentially. Primary Outcome Measures will be measured concurrently, rather than at separate time points (i.e., blood pressure and blood samples will both be taken at study onset, 30 days, 60 days and 90 days) and therefore fall within the same time points.

Study Record Dates

• First Submitted: September 10, 2019
• First Posted: February 21, 2020
• Study Start: November 15, 2020
• Primary Completion: June 30, 2024
• Study Completion: June 30, 2024
• Last Updated: November 1, 2024

Record last verified: 2023-06

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)